Convergent-Divergent nozzle problem
 

Hi everyone,

I am a student at Liverpool Uni and I am studying an aeroengines module where one of our assignments is to use the cfd package FLUENT to analyze 2D flow through a convergent divergent nozzle, I'm having some trouble with two of the conclusion questions and would really appreciate if anyone could help me.

I have completed the analysis and have included the plot as an attachment (Centreline 1 and Wall 1 refer to the initial iterations with a coarse mesh, whereas Centreline 2 and Wall 2 refer to iterations with a refined mesh and a higher tolerance. The 1D analysis was done through calculation) The analysis was done assuming inviscid and compressible flow. Here are the questions:

* What are the main conclusions you draw from the plot?
There was another question regarding improving the accuracy of the analysis so I didn't think this question would also involve it. I thought it was to say the mach number increases through the nozzle and that the 1d analysis is reasonably accurate at judging the mach number. Any other ideas?

* What physical phenomena has our analysis neglected which may be important in the nozzle problem?
I assumed this was referring to a shockwave, the problem was set up with an inlet stagnation pressure of 110,000 Pa and an outlet static pressure 3738.9 Pa so I was confused as I thought it would not need to expand. Another option would be viscous flow however there was a seperate question regarding this aswell asking if the analysis is more accurate near the centreline or the wall.

Like I said before any help would be hugely apreciated!

Plz tell me the terms, static pressure, total pressure, static temperature and total temperature with respect to convergent divergent nozzle I m so worried plzz help me I will be thankful

There are lot of materials on isentropic CD nozzle. Refer any compressible fluid dynamics or gas dynamics book for good explanation.